Question

Ms. Lisa Monnin is the budget director for Nexus Media Inc. She would like to compare the daily travel expenses for the sales staff and the audit staff. She collected the following sample information.

Sales ($)	130	136	147	161	132	147
Audit ($)	131	103	132	132	140	107	132

At the 0.05 significance level, can she conclude that the mean daily expenses are greater for the sales staff than the audit staff?

  

1.	State the decision rule. (Round your answer to 3 decimal places.)

Reject H0 if t >

2.	Compute the pooled estimate of the population variance. (Round your answer to 2 decimal places.)

Pooled variance

3.	Compute the test statistic. (Round your answer to 3 decimal places.)

Value of the test statistic

4.	State your decision about the null hypothesis.

(Click to select)Do not rejectReject H₀ : μ_s ≤ μ_a

5.	Estimate the p-value. (Round your answers to 3 decimal places.)

p-value

(Click to select)between 0.01 and 0.025between 0.05 and 0.1less than 0.01between 0.025 and 0.05

Answer 1

1)

degree of freedom   v=		(n1+n2-2)=	11.000
for 0.05 level ,right tail test &11 df, critical t=			1.796
Decision rule :                   reject Ho if test statistic t>1.796

2)

	sales		audit
x1    =	142.17	x2      =	125.29
s1    =	11.75	s2      =	14.23
n1    =	6	n2     =	7
Pooled Variance Sp2=((n1-1)s21+(n2-1)*s22)/(n1+n2-2)=				173.30

3)

standard error se =Sp*√(1/n1+1/n2)=			7.3239
test stat t =(x1-x2-Δo)/Se=		2.305

4)

reject Ho

5)

p value is between 0.01 and 0.025